Method of monitoring at least one printing parameter of printer, method of determining and sending at least one printing parameter of a printer, printing system and printer

ABSTRACT

A printing system having a control arrangement and at least one printer, which are connected to each other via a communications network, in which the printer comprises the following components:
         a sensor arrangement with at least one sensor for registering at least one printing parameter,   an encoding unit coupled to the sensor arrangement for encoding a printing parameter message belonging to a printing parameter determined by the sensor arrangement,   a data transmitting unit, which is connected to the communications network, for sending the printing parameter message,   in which the control arrangement comprises the following components:   a data receiving unit, which is connected to the communications network, for receiving the printing parameter message,   a decoding unit for decoding the printing parameter message,   a printing parameter monitoring unit, coupled to the decoding unit, for monitoring the printing parameter received.

This application is a continuation of U.S. application Ser. No.10/416,198, filed May 8, 2003, which was the National Stage ofInternational Application No. PCT/DE01/04178, filed Nov. 9, 2001, whichwas the PCT application claiming priority to German Application 100 56060.1, filed Nov. 11, 2000, all of which are incorporated by referenceherein.

At the current time, data to be printed are increasingly transmitted indigital form over great distances with the aid of data transmissionmedia such as telephone lines, directional radio or satellite links.

The purpose of this transmission is to print out the data transmitted ina printer as receiver.

It is the intention of the transmitter, that is to say of a transmittingarrangement, to configure the printing reproduction in the printer asreceiver in such a way that it agrees as accurately as possible with theversion of the transmitter, that is to say the version which is presentin the transmitting arrangement.

According to the prior art, however, only confirmation of the properreception of the data on the receiver side is provided.

However, an apparatus of this type is not suitable to ensure agreementbetween a printout on the receiver side and a desired printout,irrespective of the printing conditions on the receiver side.

Accordingly, the transmitting arrangement has no kind of control overthe agreement between the printout on the receiver side and a printouton the transmitter side.

Even if both the transmitting arrangement and the printer use the samedata, there are still various possibilities as to why the two printoutscan be different from each other, for example

-   -   differently calibrated printers,    -   different printing materials, designated the printing medium        below, or    -   faults in the printout.

For this reason, it has hitherto been impossible for the transmitter toensure agreement between a printout and a desired printout.

The invention is therefore based on the problem of monitoring a printoutin an improved way via a communications network.

In a method of monitoring at least one printing parameter of a printer,the printing parameter is registered.

In the following text, a printing parameter is to be understood to meana parameter which characterizes the print from the printer, for example

-   -   the presence of printing material (of a printing medium) in the        printer;    -   the speed and/or the direction of the transport of the printing        medium in the printer;    -   adequate agreement of the color reproduction on the printing        medium with a predefined desired color reproduction;    -   the homogeneity of the information printed out.

The printing parameter can also be determined from at least some of theparameters mentioned above, for example by means of processing theparameters, in order to obtain from these metaparameters, which have acompressed information content as compared with the parameters mentionedabove.

The printing parameter registered is encoded to form a printingparameter message, for example in accordance with a predefinedcommunications protocol, preferably in accordance with the TransportControl Protocol (TCP) and/or the Internet Protocol (IP).

In principle, according to the invention any desired number of printingparameters can be determined and encoded to form one or more printingparameter messages.

In a further step, the printing parameter message is transmitted by theprinter to a control arrangement via a communications network, forexample a fixed communications network or a mobile radio network.Alternatively, the communications network can also be a localcommunications network (Local Area Network, LAN). Within the context ofthe transmission of the printing parameter message, any desiredcommunications protocol can be used.

After transmission has been carried out, the printing parameter messagereceived by the control arrangement is decoded. By means of thedecoding, the printing parameter contained in the printing parametermessage is determined by the control arrangement and is thereforeavailable centrally in the control arrangement.

The printing parameter is monitored by the control arrangement. Thecontrol arrangement is, for example, a central control computer, whichis coupled to the printer via the communications network.

The monitoring can be carried out, for example, by a predefined desiredcourse of the printing parameter over time being monitored.Alternatively, the monitoring can be a threshold value comparison, as afunction of whose result an appropriate action is triggered.

Depending on the printing parameter, a control instruction can begenerated by the control arrangement to control the printer. The controlinstruction can be encoded by the control arrangement to form a controlinstruction message, preferably in accordance with the communicationsprotocol already used for encoding the printing parameter message.According to this configuration of the invention, the controlinstruction message is transmitted to the printer via the communicationsnetwork. The control instruction message is received by the printer anddecoded by the latter, with which message the control instruction isdetermined. The printer is then controlled in accordance with thecontrol instruction determined, that is to say individual components,for example the drive motor for producing the advance of the printingmedium, the printing nozzles, etc, are activated.

By means of this configuration of the invention, the transmitter ofdigital data, that is to say the control arrangement, is placed in theposition not only of monitoring the proper reception of its transmittedprinting data but also of monitoring the proper printout of the same ona printer at the receiver and even of controlling it.

According to a further configuration of the invention, the printingparameter is compared with the predefined criterion and the controlinstruction is generated as a function of the comparison result. Forexample, the color composition of the color printed on the printingmedium by the printer can be controlled by means of the controlarrangement, or else the printer can be calibrated, generally adjusted,with regard to further aspects.

According to a preferred configuration, the print from the printercharacterized by the printing parameter is carried out on the basis ofprinting data which has been transmitted via the communications systemby means of a transmitting arrangement. The transmitting arrangementcan, in particular, have the control arrangement.

The printing data is preferably printed out by means of a furtherprinter before being transmitted to the printer and, by using thisprintout, a predefined criterion for the comparison of the printoutparameter is determined.

The predefined criterion preferably depends on at least one desiredvalue, which is selected from the following group:

-   -   a desired transport value with respect to the speed and/or the        transport of the printing material in the printer;    -   a desired color value with respect to the colorimetric agreement        of the color reproduction on the printing material with a        predefined desired reproduction; and    -   a desired homogeneity value with respect to the homogeneity of        the information printed out.

The comparison between the printer parameter and the predefinedcriterion is preferably carried out by the control arrangement.Alternatively, the comparison can also be implemented in the printeritself in the form of a computer program to be executed, and thecomparison result is in this case transmitted to the control arrangementas the printing parameter.

In a method of determining and sending at least one printing parameterof a printer, the printing parameter characterizing the print from theprinter, at least one printing parameter is registered. Furthermore, theprinting parameter registered is encoded to form a printing parametermessage, and the printing parameter message is sent to a controlarrangement via a communications network.

The encoded information can be transmitted via the Internet/Intranet ascommunications network.

Furthermore, a printing system is provided having a control arrangementand at least one printer, which are connected to each other via acommunications network, in which the printer comprises the followingcomponents:

-   -   a sensor arrangement with at least one sensor for registering at        least one printing parameter,    -   an encoding unit coupled to the sensor arrangement for encoding        a printing parameter message belonging to a printing parameter        determined by the sensor arrangement,    -   a data transmitting unit, which is connected to the        communications network, for sending the printing parameter        message,    -   in which the control arrangement comprises the following        components:    -   a data receiving unit, which is connected to the communications        network, for receiving the printing parameter message,    -   a decoding unit for decoding the printing parameter message,    -   a printing parameter monitoring unit, coupled to the decoding        unit, for monitoring the printing parameter received.

The control arrangement can additionally comprise the followingcomponents:

-   -   a control instruction generation unit, with which a control        instruction is generated as a function of at least one printing        parameter received in order to control the printer,    -   the encoding unit being set up to encode a control instruction        message from the control instruction, and    -   a data transmitting unit, which is connected to the        communications network, for sending the control instruction        message.

According to a further preferred configuration, a further printer forprinting out the printing data transmitted to the printer by atransmitting arrangement before it is transmitted via the communicationsnetwork, and a further sensor arrangement for determining desired valuesby using the printout produced by the further printer are provided.

A comparison unit for comparing the desired values with the printerparameter is preferably provided.

According to a further configuration of the invention, the printercomprises the following components:

-   -   a data receiving unit, which is connected to the communications        network, for receiving the control instruction message,    -   the decoding unit being set up to decode the control instruction        message belonging to the control instruction, and    -   a printer control unit for controlling the printer as a function        of the control instruction.

Furthermore, the printer can have a printer control unit for controllingthe printer in accordance with a predefined control sequence.

According to a development of the invention, a sensor control unit isprovided for controlling the sensor arrangement in accordance with thepredefined control sequence.

The printer control unit and the sensor control unit can be implementedjointly in a control unit.

The control unit can pick up the measured values from the sensors,preprocess them and transmit the results to the transmitter of theprinting data via a suitable transmission medium.

This can be done in a way in which the printer accommodates control dataon the printout (for example in a marginal region of the printingmedium), which data is then measured via the sensors and is verified bythe control unit or a connected computer or the transmitter itself in adesired-actual comparison.

Furthermore, the sensor arrangement can comprise at least one of thefollowing sensors,

-   -   at least one rotary encoder for determining the transport speed        and/or the transport direction and/or the transport distance of        the printing medium in the printer,    -   at least one color sensor, and/or    -   at least one image sensor.

According to this configuration of the invention, it is advantageous touse sensors which are already present in a commercially availableprinter, which achieves a considerable saving in costs.

The sensors of the sensor arrangement do not have to be fixed to theprint head of the printer. They should be fixed at a point within theprinter at which the printed material can move the rotary encoder and,at the same time, the color sensor can carry out color measurements andthe image sensor can make image recordings.

The rotary encoder is preferably connected to the material to be printedin a suitable way, such that it is capable of measuring the directionand the speed of the movement of the said material.

Furthermore, the color sensor is set up in such a way that, by means ofcalorimetric measurement, it is capable of measuring the color of thematerial to be printed (the printing medium) at the point to be measuredwith sufficient accuracy (preferably by means of spectrophotometricmeasurement).

The image sensor can be connected to suitable optics and imageevaluation optics, so that this unit is capable of examining the printedimage for undesired inhomogeneities, in order in this way, for example,to detect blocked nozzles on the print head of an ink jet printer.

Also provided is a printer

-   -   having a sensor arrangement with at least one sensor for        registering at least one printing parameter,    -   having an encoding unit coupled to the sensor arrangement for        encoding a printing parameter message belonging to a printing        parameter determined by the sensor arrangement, and    -   having a data transmitting unit, which is connected to the        communications network, for sending the printing parameter        message.

Clearly, the invention can be seen as remote monitoring of a printout ona printer, it being possible for a control unit to be fitted to theprinter which, in turn, can be coupled to a color sensor operatingspectrophotometrically, to a rotary encoder and/or to an image sensor,and which has an interface in order to be monitored by a computerconnected to this interface via a communications network, in thesimplest case a cable, or directly via data transmission media such as acommunications network or the Internet.

By means of the invention, therefore, for the first time remotemonitoring of a printer, in particular with regard to the printingparameters that characterize the print, becomes possible.

By equipping a printer by means of suitable sensors, which monitor theprinter in relation to material transport, printed color values andprinted image, and by transmitting this data as printing parameters backto the transmitter, that is to say the control arrangement, it is nowpossible to monitor the agreement between a printout from the printer,which remains remote from the control arrangement, with the printout(desired printout) intended by the control arrangement.

The invention will be explained in more detail below using exemplaryembodiments illustrated in the appended figures.

In the figures:

FIG. 1 shows a block diagram in which a printing system according toanyone exemplary embodiment of the invention is illustrated;

FIG. 2 shows a block diagram in which a printing system according to afurther preferred exemplary embodiment is illustrated, by means of whicha comparison between the printouts on the transmitter and receiver sidecan be implemented;

FIG. 3 shows a block diagram in which a printing system according to afurther preferred embodiment is illustrated.

A printing system 100 comprises a printer 101, in principle any desirednumber of printers 101. The printer 101 is coupled to a communicationsnetwork 102, to the Internet/Intranet according to this exemplaryembodiment, and moreover to a control computer 103 as a controlarrangement, which is likewise coupled to the communications network102.

The printer 101 comprises

-   -   a transmitting/receiving unit 104,    -   a decoding/encoding unit 105 coupled to the        transmitting/receiving unit 104,    -   a control unit 106 coupled to the decoding/encoding unit 105,        and    -   a sensor arrangement 107 coupled to the control unit 106.

The sensor arrangement 107 comprises three sensors 108, 109, 110respectively coupled to the control unit 106, specifically

-   -   a rotary encoder 108,    -   a color sensor 109, and    -   an image sensor 110.

In this connection, it should be pointed out that for the case in whichthe color sensor 109 operates sufficiently accurately, it is possible todispense with the image sensor 110, since failure of one or more nozzlesof the printer 101 can also be detected by means of a color change onthe printing medium.

Alternatively, the printer 101 can be configured as a monochromeprinter, so that in this case it is possible to dispense with the colorsensor 109.

The rotary encoder 108 is connected in a suitable way to the material tobe printed such that it can measure the direction and the speed of themovement of the material in the printer 101.

The rotary encoder 108 according to this exemplary embodiment is acommercially available component, which is set up in such a way that itis capable of generating a train of electrical signals given thepresence of a rotational movement. From the type and the speed of thesesignals, the direction and the speed of the rotational movement aredetermined.

The rotary encoder 108 comprises a shaft for transmitting the rotationalmovement, a disc fitted to this shaft and having appropriate slotstherein, and a sensor which, with the aid of a light barrier, generatesan electrical pulse as such a slot passes through the light barrier.

Two light barriers are preferably arranged in a rotary encoder 108 inthe printer 101 in such a way that the pulses generated by them have aphase shift. To this end, it is alternatively possible, but lesspreferred, for two rotary encoders to be used as well. The direction ofrotation of the printing medium in the printer 101 can then be derivedfrom the sign of the phase shift.

In order to be able to draw conclusions about the material movement withthe aid of the rotary encoder 108, the shaft contained in the rotaryencoder 108 is coupled to a wheel which is pressed onto the printingmedium running through the printer 101.

The wheel is provided with a rubber-like covering, in order to ensurebetter friction with respect to the printing medium. The contactpressure is chosen such that no slip occurs between wheel and theprinting medium and, at the same time, the printing medium is nothampered in its normal movement.

By means of suitable arrangement of the further sensors 109, 110 andtheir coupling to the wheel, it is also possible according to theinvention to use the wheel to set a constant distance between thesensors and the printing medium, irrespective of the material thicknessof the printing medium used.

By counting the number of pulses per unit time supplied to it by therotary encoder 108, and by comparing the phase angle of the two signals,the control unit 106 connected to the rotary encoder 108 can obtain thefollowing information:

-   -   the speed of the printing medium in the printer 101 (from the        number of pulses per unit time and from the knowledge of the        circumference of the wheel);    -   the direction of the material transport, that is to say of the        transport of the printing medium in the printer 101 (from the        phase angle of the two signals);    -   the distance covered, that is to say the material consumption up        to this point (number of pulses and wheel circumference).

In interaction with the further sensors 109, 110 of the sensorarrangement 107, the control unit 106 can, for example, arrange forcolor measurements to be carried out at best when the material to beprinted has just come to a standstill in the printer. In this way, ahigher accuracy of the color measurement is achieved, using the colorsensor 109 and the rotary encoder 108.

The color applied to the printing medium by means of the printer 101 ismeasured sufficiently accurately by means of spectrophotometricmeasurements, using the color sensor 109.

According to this exemplary embodiment, therefore, a color sensor 109that operates spectrophotometrically is used.

The color sensor 109 that operates spectrophotometrically is set up insuch a way that it is capable of measuring the intensity of the lightreflected from an original, to the printing medium, at variouswavelengths.

These individual intensities are then used in accordance with a rule(for example in accordance with DIN 5033) to calculate the resultantcolor in the XYZ color space.

For the color sensor 109 used in accordance with this exemplaryembodiment, it is advantageous for said sensor to have a most compactoverall form and, to the extent possible, to have its own light sourcefor illuminating the region to be measured on the printing medium, inorder to be independent of external illumination.

Furthermore, it is advantageous for the original to be located at aconstant distance from the color sensor 109, in order to ensure constantmeasurement conditions, even if, for example, the thickness of theprinting medium changes.

This may be achieved, for example, by the color sensor 109 being firmlycoupled to the wheel of the rotary encoder 108 described above, saidwheel running on the surface of the material of the printing medium andtherefore having a defined and constant distance between the surface ofthe printing medium and the axis.

According to this exemplary embodiment, the image sensor 110 used is atwo-dimensional array of light-sensitive cells on a CCD basis or CMOSbasis, such as are also used in a digital camera, for example.

The image sensor 110 is set up to examine the printed image forundesired inhomogeneities, in order in this way, for example, todetermine blocked nozzles on the print head of the printer, preferablyan ink jet printer.

In conjunction with suitable optics, in this way microscopic recordingsof the printed regions on the printing medium can be made.

An image evaluation unit (not illustrated) provided in the printer 101or in the control computer 103, in conjunction with appropriatelydesigned test patterns, can determine the following states:

-   -   the readiness for operation or the failure of individual nozzles        of the print heads of the printer 101,    -   the correctness of the horizontal and vertical alignment of the        print heads of the printer 101,    -   the magnitude of the deviation of the horizontal and vertical        alignment of the print heads of the printer 101, if there is no        correct alignment of the print heads of the printer 101,    -   the straight emergence of the printing medium in the printer        101.

The image evaluation can thus be carried out directly in the controlunit 106 connected to the sensor arrangement 107, so that only theresults of this evaluation are transmitted to the control computer 103.

Another possibility is to send the image data in complete form to theevaluation, that is to say to transmit it to the control computer 103,in compressed or uncompressed form.

The control unit 106 has the following tasks:

-   -   control, monitoring and coordination of the sensors 108, 109,        110; this means that the control unit 106, for example by        monitoring the rotary encoder 108, determines the distance        through which the printing medium has moved, in order in this        way to trigger, that is to say to start, a color measurement by        the color sensor 108 and a recording by the image sensor 109 at        equidistant, predefinable positions; likewise, by evaluating the        rotary encoder signals, the control unit 106 can determine        misbehavior of the printer 101, for example excessively fast        and/or continuous unwinding of the printing medium;    -   conditioning the results transmitted by these sensors 108, 109,        110, for example by preprocessing the data (for example        filtering, averaging, statistical analysis, etc); by monitoring        the color sensor 109, the control unit 106 can detect the start        of the test strip on the printing medium, if said strip is        encoded by means of a specific predetermined color; the same can        be done via the image sensor 110, if the start of the test strip        is identified by a specific pattern; the control unit 106 can        reduce the data supplied by the sensors 108, 109, 110 to the        quantity relevant to the user, that is to say compress said data        in accordance with any desired predefined compression method. In        addition, the control unit 106 can obtain new information by        means of the combination of data which is generated        simultaneously by two or three sensors 108, 109, 110 and        received by the control unit 106, for example by means of        combination (addition, subtraction, correlation, etc.) of the        sensor signals respectively received.    -   communication with the control computer 103 which controls the        printer 101, via the decoder/encoder unit 105 and the        transmitting/receiving unit 104 of the printer 101, as will be        explained in more detail below; the control unit 106        communicates via an interface, according to this exemplary        embodiment formed by the decoder/encoder unit 105 and the        transmitting/receiving unit 104 of the printer 101,        alternatively for example via a network connection, via the        Internet, via a serial or parallel interface, with a connected        computer, the control computer 103; the latter is capable of        receiving and evaluating information from the control unit 106,        of triggering specific states or actions (for example resetting,        initialization) in the control unit 106, and also comparing the        measured values with the desired values or with values from a        previous measurement.

The control computer 103 is coupled to the communications network 102and comprises

-   -   a transmitting/receiving unit 111,    -   a decoder/encoder unit 112 coupled to the transmitting/receiving        unit 111, and    -   a monitoring and control instruction generating unit 113 coupled        to the decoder/encoder unit 112.

In the further text, the sequence of a print according to this exemplaryembodiment of the invention will be explained with reference to FIG. 1.

Printing data to be printed is generated by the control computer 103,encoded by the decoder/encoder unit 112 in accordance with the TCP/IPprotocols to form one or more printing data messages and, by means ofthe transmitting/receiving unit 111 of the control computer 103, aresent to the communications network 102 and thus transmitted to theprinter 101 on the receiver side.

The encoded printing data messages are received by thetransmitting/receiving unit 104 and decoded by the decoding/encodingunit 105 of the printer 101, the printing data to be printed beingdetermined thereby.

Then, at least part of the printing data to be printed is printed on aprinting medium guided into the printer 101.

At least part of the information printed on the printing medium andinformation about the printing operation itself is registered by meansof the sensors 108, 109, 110 of the sensor arrangement 107, subjected tosignal processing and supplied to the control unit 106. The printingparameters determined in this way are supplied to the decoding/encodingunit 105 of the printer 101, by which the printing parameters areencoded to form a printing parameter message which, by means of thetransmitting/receiving unit 104 of the printer 101, is sent to thecommunications network 102 and thus transmitted to the control computer103.

After the printing parameter message has been received by the controlcomputer 103, the printing parameter message is decoded and the printingparameters are determined and analyzed, that is to say evaluated,according to this exemplary embodiment by means of a comparison with oneor more desired values belonging to the printing parameter respectivelytaken into account.

Depending on the analysis result, that is to say in the simple casedepending on the comparison result, a control instruction is generatedby the monitoring and control instruction generating unit 113 and, ascan be seen, represents a command for the activation of the printer 101.

The control instruction is supplied to the decoding/encoding unit 112,by which it is encoded to form a control instruction message. Thecontrol instruction message is sent to the communications network 102 bymeans of the transmitting/receiving unit 111 of the control computer103, and thus transmitted to the printer 101.

The control instruction message received is decoded by means of thedecoding/encoding unit 105 of the printer 101, and the controlinstruction determined is supplied to the control unit 106 of theprinter 101.

The control unit 106 in turn controls the printer 101 on the basis ofthe control instruction received.

The desired value or the plurality of desired values belonging to theprinting parameters, are preferably determined by the digital datatransmitted to the printer 101 by the control arrangement 103 beingprinted out by means of a further printer (not illustrated) even beforetheir transmission to the printer 101, as will be explained in moredetail below. In relation to the communications network 102, thisfurther printer is located on the side of the transmitter, that is tosay the control arrangement 103.

The printed image produced in this way on the side of the transmittercan be measured, for example before the transmission of the printingdata, by a commercially available color measuring instrument, preferablya spectrophotometer, and then converted into the data format that can besent via the communications network 102, in particular for example inaccordance with a predefined communications protocol, preferably inaccordance with the Transport Control Protocol (TCP) and/or the InternetProtocol (IP).

For this purpose, use is preferably made of a preferred exemplaryembodiment of a printing system illustrated according to FIG. 2.

According to FIG. 2, a transmitter 114 which, in particular, can have acontrol arrangement corresponding to the control arrangement 103 fromFIG. 1, transmits digital printing data 15 via a communications network(not illustrated) to a receiver 116, for example in the form of theprinter 101 from FIG. 1. At the receiver 116, the printing data 115received is printed out. The printout produced is evaluated by a sensorarrangement 117 that is monitored by a control unit and which can beconstructed in a manner analogous to the sensor arrangement 107 fromFIG. 1 that is monitored by the control unit 106, a printing parameterbeing produced in a manner analogous to the embodiment illustrated inFIG. 1.

In parallel with the transmission of the printing data 115 from thetransmitter 114 to the receiver 116, said data is transmitted, accordingto FIG. 2, to a further printer 118, which is likewise coupled to asensor arrangement 119 monitored by means of a control unit. In relationto the communications network, the further printer 118 is preferablyarranged on the side of the transmitter 114.

The sensor arrangements 117, 119 preferably comprise, in a manneranalogous to the embodiment illustrated in FIG. 1, a rotary encoder fordetermining the transport speed, transport direction and/or transportdistance of the printing medium in the respective printer 116 and 118, acolor sensor and an image sensor. The color sensor used is preferably acolor sensor that operates spectrophotometrically. By means of thesensor arrangements 117, 119, in a manner analogous to the embodimentillustrated in FIG. 1, an evaluation of the printed images supplied bythe respective printer 116 and 118 is carried out, generatingcorresponding sensor data 120 and 121.

According to FIG. 2, this sensor data 120 or 121 is supplied to acomparison unit 122 which, in relation to the communications networkthat links the transmitter 114 and receiver 116, can be arranged eitheron the side of the transmitter 114 or on the side of the receiver 116.In this way, a comparison of the printed result produced on the receiverside with the printed result present on the transmitter side is carriedout, so that the comparison result is available to the transmitter. Thesensor data 120 determined on the transmitter side by the sensorarrangement 119 can in this case be used as desired values for thecomparison of the printout on the receiver side with the printout on thetransmitter side, that is to say for a comparison between the printingparameters determined on the transmitter and receiver sides.

In detail, these desired values can be determined as follows for acomparison, to be carried out in order to monitor the printing parameterdetermined on the receiver side, with this parameter:

The desired values with respect to the direction and the speed of thetransport of printing medium in the printer 116 are preferablydetermined in accordance with the printing system used during the designor the configuration of the sensor unit. At this time, it is alreadyknown in which direction the printing material must move and at whatspeed.

The desired values with respect to the colorimetric agreement of thecalorimetric printing parameters to be monitored are preferablydetermined by the digital data to be transmitted being printed out, forexample on an ink jet printing system, at the transmitter 114 or at thecontrol arrangement 103 before being transmitted. For this purpose, theprinting system 100 preferably has just the same sensors 108-110 on thetransmitter side as on the receiver side. Before being sent to thereceiver, the document to be sent is therefore printed out on thetransmitter side, in order in this way to determine the printingparameters. For this purpose, the data is printed out as described aboveand measured by a commercially available color measuring instrument,preferably a spectrophotometer, and then converted into the data formatthat can be sent.

The desired values with respect to the homogeneity of the printout arepreferably defined by means of a definition of the desired state. Thedesired state preferably used is a smooth area in the test pattern whichis not interrupted by white lines, which can be caused by missingnozzles or nozzles not in operation. According to a further preferredembodiment, a test pattern is defined by using lines which areassociated uniquely with the individual nozzles of an ink jet printer.This test pattern is then examined for the presence of the expectedlines, for example by an image processing unit.

The embodiment of a printing system illustrated in FIG. 3 corresponds tothe printing system illustrated in FIG. 2 to the extent that printingdata 124 are transmitted by a transmitter 123 to a receiver 125 and, byusing a printout produced on the receiver side, by means of a sensorarrangement 126, which is in turn monitored by a control unit, sensordata 127 is transmitted to a comparison unit 128. However, the desiredvalues with regard to the colorimetric agreement, required for thecomparison, are received by a printing machine 129, which suppliescorresponding color measured values to the comparison unit 128.

If the printer is a system which is used for proof purposes, that is tosay to simulate the print on a printing machine, the desired value withrespect to the calorimetric agreement is preferably determined directlyfrom the color behavior of this printing machine, according to FIG. 3.The color behavior of a printing machine can be registered in a knownway in what is known as an ICC color profile (ICC—International ColorConsortium), in that, for example, an IT8/7.3 Testform according toISO/DIS 12640, which has been printed on this printing machine, ismeasured calorimetrically. Such a profile makes it possible to determinethe color results which have been achieved when specific combinations ofprinting inks are used on this printing machine. With the aid of such aprofile, therefore, it is possible to determine those calorimetricvalues which must be achieved during the simulation of this printingmachine on an ink jet printing system. These calorimetric values canthen be used as desired values with respect to the calorimetricagreement. The block diagram of an appropriate printing system isillustrated schematically in FIG. 3.

1. A method of monitoring at least one printing parameter of a printercomprising: establishing a printing environment with at least oneprinter and a control arrangement coupled via a communications network;measuring one or more printing parameters of a material to be printed bythe at least one printer using a rotary encoder, said measuringcomprising: transmitting the rotational movement of the material using arotary encoder having a shaft; generating a plurality of electricalpulses by rotating a disc coupled to the shaft having a plurality ofslots through a light barrier; and deriving the one or more printingparameters from the phase shift of the plurality of electrical pulses;encoding the one or more printing parameter to form a printing parametermessage; transmitting the printing parameter message using a datatransmitting unit coupled to the communications network, whereinmeasuring one or more printing parameters of a material comprisesmeasuring any of the direction of a material transport and printingmaterial consumption; monitoring the printing parameter using the stepsof: receiving the printing parameter message via a data receiving unit,wherein the data receiving unit is coupled to the communicationsnetwork; decoding the printer parameter message using a decoding unit;and monitoring the printing parameter received using a printingparameter monitoring unit, the printing parameter monitoring unitcoupled to the decoding unit; determining states using an imageevaluation unit configured to determine the following states: thecorrectness of the horizontal alignment of a print head; the correctnessof the vertical alignment of said print head; the magnitude of deviationof the horizontal alignment of said print head; the magnitude ofdeviation of the vertical alignment of said print head; and the straightemergence of a printing medium from said printer upon determining saidstates, printing the material based on all said states on at least oneadditional printing system, forming a printout; and determining printvalue criteria using the printout and a sensor arrangement, wherein theprint value criteria are used in a comparison of the printing parameter.2. The method of monitoring at least one printing parameter according toclaim 1, further comprising: generating a control instruction as afunction of at least one printing parameter received in order to controlthe printer, encoding a control instruction message from said controlinstruction, and sending said control instruction message via a datatransmitting arrangement coupled connected to the communicationsnetwork.
 3. The method of monitoring at least one printing parameteraccording to claim 2, further comprising: receiving the controlinstruction message via a data receiving unit in the printer; decodingthe control instruction message via a decoding unit in the printer,forming a decoded control instruction; and controlling the printer as afunction of the decoded control instruction.
 4. The method of monitoringat least one printing parameter according to claim 3, further comprisingusing a predefined control sequence for controlling the printer as afunction of the decoded control instruction.
 5. The method of monitoringat least one printing parameter according to claim 1, further comprisingcomparing the desired values with the printing parameter being provided.6. The method of monitoring at least one printing parameter according toclaim 1, further comprising controlling the rotary encoder with a sensorcontrol unit in accordance with a predefined control sequence.
 7. Amethod of monitoring at least one printing parameter of a printer,comprising: providing a printer coupled with a control arrangement via acommunications network; registering at least one printing parameterusing a color sensor that operates spectrophotometrically; encoding theprinting parameter using an encoding unit coupled to the color sensor,forming a printing parameter message; transmitting the printingparameter message using a data transmitting unit, wherein the datatransmitting unit is coupled to the communications network; receiving,decoding and monitoring the printing parameter message using the controlarraignment, further comprising: receiving the printing parametermessage with a data receiving unit coupled to the communicationsnetwork; decoding the printing parameter message; and monitoring theprinting parameter received; determining states using an imageevaluation unit configured to determine the following states: thecorrectness of the horizontal alignment of a print head; the correctnessof the vertical alignment of said print head; the magnitude of deviationof the horizontal alignment of said print head; the magnitude ofdeviation of the vertical alignment of said print head; and the straightemergence of a printing medium from said printer; upon determining saidstates, printing out the printing data based on all said states on atleast one additional printer before it is transmitted via thecommunications network, wherein said at least one additional printercomprises at least one additional sensor arrangement; and determiningdesired values using said at least one additional sensor arrangementusing the printout produced by said at least one additional printer,wherein a predetermined criterion is determined for a comparison of theprinting parameter.
 8. The method of monitoring at least one printingparameter according to claim 7, further comprising: generating a controlinstruction as a function of at least one printing parameter received inorder to control the printer, encoding a control instruction messagefrom said control instruction, and sending said control instructionmessage via a data transmitting arrangement coupled connected to thecommunications network.
 9. The method of monitoring at least oneprinting parameter according to claim 8, said transmitting arrangementcomprising the control arrangement.
 10. The method of monitoring atleast one printing parameter according to claim 7, further comprisingcomparing the desired values with the printing parameter being provided.11. The method of monitoring at least one printing parameter accordingto claim 7, further comprising: receiving the control instructionmessage via a data receiving unit in the printer; decoding the controlinstruction message via a decoding unit in the printer, forming adecoded control instruction; and controlling the printer as a functionof the decoded control instruction.
 12. The method of monitoring atleast one printing parameter according to claim 7, further comprisingusing a predefined control sequence for controlling the printer as afunction of the decoded control instruction.
 13. The method ofmonitoring at least one printing parameter according to claim 7, furthercomprising configuring the color sensor is configured with a lightsource to illuminate a region of a printing medium to be measured. 14.The method of monitoring at least one printing parameter according toclaim 7, further comprising configuring the color sensor at a constantdistance from a printing medium to be measured.
 15. A method ofmonitoring at least one printing parameter of a printer comprising:providing a printing environment having at least one printer and acontrol arrangement coupled via a communications network; examining aprinted image for undesired inhomogeneities using a image sensor,forming at least one printing parameter; encoding the printing parameterusing an encoding unit coupled to the image sensor, forming a printingparameter message, transmitting the printing parameter message using adata transmitting unit, which is coupled to the communications network,said transmitting comprising: receiving the printing parameter messagewith a data receiving unit coupled to the communications network;decoding the printing parameter message; and monitoring the printingparameter received; determining states using an image evaluation unitconfigured to determine the following states: the correctness of thehorizontal alignment of a print head; the correctness of the verticalalignment of said print head; the magnitude of deviation of thehorizontal alignment of said print head; the magnitude of deviation ofthe vertical alignment of said print head; and the straight emergence ofa printing medium from said printer; upon determining said states,printing out the printing data based on all said states on at least oneadditional printer before it is transmitted via the communicationsnetwork; and determining desired values using at least one additionalsensor arrangement using the printout produced by said at least oneadditional printer, wherein a predetermined criterion is determined fora comparison of the printing parameter.
 16. The method of monitoring atleast one printing parameter according to claim 15, further comprising:generating a control instruction as a function of at least one printingparameter received in order to control the printer, encoding a controlinstruction message from said control instruction, and sending saidcontrol instruction message via a data transmitting arrangement coupledconnected to the communications network.
 17. The method of monitoring atleast one printing parameter according to claim 16, said transmittingarrangement comprising the control arrangement.
 18. The method ofmonitoring at least one printing parameter according to claim 15,further comprising comparing the desired values with the printingparameter being provided with a comparison unit.
 19. The method ofmonitoring at least one printing parameter according to claim 15,further comprising: receiving the control instruction message via a datareceiving unit in the printer; decoding the control instruction messagevia a decoding unit in the printer, forming a decoded controlinstruction; and controlling the printer as a function of the decodedcontrol instruction.
 20. The method of monitoring at least one printingparameter according to claim 15, further comprising controlling theprinter in accordance with a predefined control sequence with a printercontrol unit.
 21. The method of monitoring at least one printingparameter according to claim 15, the image sensor comprising atwo-dimensional array of light sensitive cells.
 22. The method ofmonitoring at least one printing parameter according to claim 15, theimage sensor comprising a two-dimensional array of CCD sensors.
 23. Themethod of monitoring at least one printing parameter according to claim15, the image sensor comprising a two-dimensional array of CMOS sensors.